Why did you initially open the crank case?New parts installed?

Floater wrote:

Thanks for the interest from each responder.   I attached another clip to demonstrate the slight sound when the piston is on the down stroke and then I push on it.  It’s the same with both pistons.  I did use assembly lube when installing the bearing retainers which may be slightly dampening the sound.

I can not isolate the original noise as to TDC or BDC or even which or both pistons.

The rings don’t seem tight at the top of the cylinder.

It does feel like the crank could be hitting; but I can’t understand how that could happen.

Listen careful:  https://youtube.com/shorts/Q9VXua7IryQ?feature=share

I think what you all are saying is: this is not normal & the cases must be opened again to rectify the problem.

Do both pistons make the same noise when this test is applied?  Sure seems like something is wrong with either the rod bearings or wrist pin bearings…

Floater wrote:

I found it.  The center bearing had a piece of crude.  See the attached link if you’re interested.

https://youtube.com/shorts/NCl0QYGJ19A?feature=share

 

Thanks to all that posted.

I hear that noise but fear that is not your main issue.  You are able to push those pistons down slightly which would seem to indicate some slop in the rod or wrist pin bearings…

Yes, what both Tubs and Dale said … that has to be fixed.  I’m betting on the wrong size needles. Your last video tells the tale… there is slack motion in the crankshaft to piston connection.

Joe B